Nut and method of manufacturing the same



April 7, 1942. A. YOUNG NUT AND METHOD OF MANUFACTURING THE SAME FiledMay 3. 1940 ATTORNEY Patented Apr. 7, 1942 NUTAND METHOD onMANUFACTURING THE SAME Leonard .A. .Young, De troit, Mich.Application-May. 3, 1940, Srial No. 333,191

- 3 Claims.

The present invention relates to a threaded nut or the likeand to anovelmethod of forming .the same.

It. is a principalobject of the invention to pro- .vide. a threaded nutor the like and a novel method of forming the same in which the threadsand the body contours of the nutare formed simultaneously in a singleupsetting operation.

Another object of the invention is to provide a threaded nut or the likein which thethreaded .portion is provided with slightly tapered wallsandan annular flange is formed adjacent the .endof the threaded portionhaving the greatest diameter, said annular flange and the taperedthreaded opening cooperating to securely lock the nut on a bolt andprevent unintended disengagement thereof.

A further object of the invention is to provide a threaded nut and animproved method of forming the same which is particularly charand theelimination of a large amount of scrap material, the method beingfurther characterized in that much labor and material handling, as wellasnumerous separate machine operations, vare eliminated.

'I'I'he present application is related to the disclosures in Patent No.2,199,007 on Jointed nut .andlmethod of making same, filed in the nameof John M. Oldham and assigned to me, and to .my co-pending applicationSerial No. 236,587 entitled fMethod of uniting metal surfaces. thispatent and in my said co-pending application there is disclosed amachine nut and a methodof forming the same and such nuts may be madeaccording to the method herein set forth.

The present invention is particularly but not exclusively applicable tothe formation of threaded nuts from relatively soft metals such, forexample, as copper, lead, brass, aluminum, and the like, or the softalloys of such metals or other metals. These metals are characterized inthat they are. more readily deformable under pressure than are someother materials, such for example as the ferrous materials. It is to beunderstood, however, that the invention is not limited strictly to theuse of such materials as it is within the purview of the presentinvention to use any metal which is deformable under pressure and fromwhich it may be desired to form a threaded nut.

Other objects and advantages of this invention will appear in thefollowing descriptionand appended claims, reference being had to theaccompanyingdrawing forming a part. of thisspeci- .acterized by aneconomical use of the material ficationnwherein like. referencecharacters designate corresponding 'parts in the several views, "and inwhich:

Fig.-1-is a plan view of a fiatblank which may be used in-aninitialstage of the method herein disclosed;

Fig. 2- is a view in perspective of the blank shownin Fig. 1foldedupon-itself and joined to provide a hollowsubstantiallycylindrical blank;

Fig. 3 is a-view .in perspective .of a completed .machine. nutembodyingthepresent invention;

Fig. 4 is a section taken substantially on the line 4-4 of Fig: 3;

Fig. 5. is a fragmentary'section' with parts .broken (away showing anupsetting die and a formed nut at the. completion of the upsettingoperation; I

Fig. 6.isa.fragmentary sectionshowing the upsetting the and a portion ofthe press the-parts ,of the die being shown in their relative positionsafter completion of the upsetting operation and .ejection'of the nutfrom. the die, the parts being shown .intheir relative'positionspreparatory to receiving another blank;

Fig. 7 is a fragmentary view partially in section .showing the upsettingdieand the mechanism for controlling actuationof the thread-formingmandrel; and I Fig. 8 is a diagrammatic view illustrating a con-..trolcircuit which-may be used in accordance with the present inventionto control actuation'of the thread-forming :mandrel.

. Before explaining in detail the present inventionit is to beunderstood that the invention is not limited: in its application -to-thedetails of construction andarrangement of parts illustrated I in theaccompanying: drawing, since the invention is capable of otherembodiments and of being 7 wire, rod or barstock. The slitting of thestock is socarried; out as to provide an extending tonguel I and amating groove 12 on opposite ends of the blank 10.

'Asshown in Fig. 2,.the blank lllis folded .upon .itself to form;hollow. substantially cylindrical blank in which the tongue I I. .isreceived inithe groove 12 and the ends ofthe blank mate at the matingshoulder surfaces l3. The cylindrical blank as shown in Fig. 2 is theform in which the blank is preferably used in the subsequent upsettingoperation to form the completed nut which, as shown in Figs. 3 and 4,may comprise a body portion l4 having apredetermined exterior contourwhich may be hexagonal, rectangular, square, etc., and a threadedinterior |5 which, as shown in Fig. 4, is of a slightly larger diameteradjacent one end of the nut than it is adjacent the other end thereof.This construction provides a centrally disposed tapered annulus whichtapers in a preferred embodiment of the invention to the extent ofapproximately .002 to .003 of an inch per one-half inch of length of thetapered opening.

The body portion M of the nut is provided with annular depending flangesl6 which are preferably provided adjacent the end of the threadedopening l5 which has the greatest diameter. The flanges '|6 when sodisposed form a ready means of identifying the end of the nut where thethreaded opening has the greatest diameter and also indicate the end ofthe nut which is to be first brought into engagement with a threadedbolt or stud to which the nut is intended to be attached. By thisconstruction a nut is provided which may be readily threaded on theextendingend of a threaded bolt, stud, or the like, and due to thetapered threaded opening in the nut there is a wedging action on thethreads of the threaded bolt or-stud which assists in holding the nut onsuch bolt or stud. This action is further accentuated when the flangesI6 are brought in contact with a surface adjacent an end of the threadedbolt or stud since the flanges preferably are V-shaped in crosssectionand have a sharp edge portion which will bite into such surfacewhen the nut is securely screwed onto the screw-threaded bolt or stud.

As shown in Fig. 3, in the completed nut the mating tongue II and thegroove |2 are so deformed that the parts are interlocked and thisprovides a jointed body portion on the nut which, however, is securelylocked in such a manner that the ends will not readily become separated.

In forming a nut embodying the present invention, or informing nutssimilar to those disclosed insaid Patent No. 2,199,007 and in my saidco-pending application, an upsetting die is employed which, as shown inFigs. 5, 6 and 7, comprises an anvil 20 having a tapered threadedmandrel 2| formed on the end thereof. A female upsetting or coining die22, having a knockoutplug 23 thereon, is so positioned and formedrelative to said anvil 20 that it surrounds the anvil in predeterminedspaced relation thereto. A retaining ring 24 is provided adjacent thebed plate of the machine and acts to support the female die 22 andprevent the breakage of said die due to the pressure created therein bythe upsetting operation. The female die 22 is secured to a suitablepress 25 for reciprocal movement in a substantially vertical planerelative to the anvil 20. The anvil 20 and the mandrel 2| are mountedfor movement in a spiral path which has substantially the same pitch asthe threads on the tapered threaded mandrel 2|. The movement of'theanvil 26 in the embodiment here shown'is caused by a reversing electricmotor 26 which drives a gear 21 which mates with a worm gear 28preferably formed on the end'of the anvil 20 opposite thetapered'mandrel 2| r The motor 26 is controlled by a switch 29 actuatedby a switch lever 30 which is connected with a switch lever connectingrod 3| and an auxiliary switch lever 32. Upon operation of the die 22the lever 36 is moved to actuate the switch 29 by the annular shoulder33 on the ram 34 of the press 25 and is moved synchronously with themovement of the female die 22. The lever 32 is connected through the rod3| with the lever 30 and is moved. to actuate the switch by the shoulder35 which is provided on the anvil 20. When the parts are in the positionshown in Fig. 6, the anvil 20 has been driven in its upward spiral pathto a position where the shoulder 35 contacts the lever 32 and moves itto stop the motor 26.

After the completion of the upsetting operation and when the parts ofthedie have moved into the position shown in Fig. 7, the ram 34 has beenmoved to actuate the lever 30 which starts the motor 26 which causesmovement of the anvil 26 and the mandrel 2| in a descending spiral path.This causes the mandrel 2| to be unscrewed from the formed nut I4. Whenthis movement of the anvil has been completed, the female die 22 is thenmoved upwardly and carries the nut with it until the knockout plug 23 isactuated and the nut is ejected from the female die 22. When the partshave been moved so as to bring the knockout plug into operation, thelever 30 has been carried into position where the motor 26 is reversedand the anvil 20 and mandrel 2| have been driven in an ascending spiralpath to the position shown in Fig. 6. At the completion of this upwardmovement of the anvil 20, the shoulder 35 actuates the lever 32 andshuts off the motor 26.

In Fig. 8 there is shown a diagrammatic view of the electrical circuitwhich may be employed to actuate the motor from the lever 3|! whichactuates the switch 29 as above described. It is to be'understood,however, that other types of control mechanisms or actuating devices maybe employed, if desired, instead of the electric motor and controllingswitches here shown. For example, a hydraulically actuated prime moverand control devices may be used for the purpose of moving the anvil 20and the thread-forming mandrel. Also, it is to be understood that thethread-forming mandrel and anvil 20 may be stationary, if desired, andthe female upsetting die 22 may be rotated as it is moved away from theanvil and thus free the nut from the threads on the mandrel.

In carrying out the present invention the thread-forming mandrel 2|carried by the anvil 2B is preferably formed of some metal harder thanthe metal used in forming the blank II) which is deformed by theupsetting operation.

For example, an oil impregnated type of bearing metal may be used informing the mandrel 2| for use on certain types of metals, while hardermetal may be used in other instances. The pitch and lead of the threadson the worm gear 28 should be such that the mandrel 2| and the anvil 20are rotated and moved in a descending spiral path at the same rate thatthe threadforming portion of the mandrel 2| is unscrewed from thethreads in the formed nut M.

and that the threads are pressed into a workhardened surface portion ofthe metal blank forming the nut since the walls of the annular openingof the blank I!) are formed of the surface material adjacent one surfaceof the fiat blank. As is known, this work-hardened metal the threadshave the appearance of a coined metal surface. In this way a muchsmoother and more durable thread may be formed than where it isnecessary to perform a further thread-cutting operation on the pressedmetal nut.

In addition to eliminating waste of material due to the cutting of thethreads, it will also be which comprises forming a flat blank providedwith a tongue on one end anda mating groove at the opposite end, bendingsaid blank to form a hollow substantially cylindrical member having'thetongue engaged in said groove, placing said blank in an upsetting diehaving a threaded mandrel therein and upsetting said blank to interlocksaid tongue and groove and to form from the blank a nut having apredetermined exterior I contour and a threaded tapered opening,removing said threaded mandrel from said nut, and thereafter ejectingsaid nut from the upsetting die.

2. The method of forming a threaded nut which includes the novel step ofsubjecting a hollow metallic blank to pressures between an upsetting dieand an anvil having a threaded portion extending into the die, saidpressures bein sufficient to cause it to flow and conform to the.

contour of said upsetting die, thereafter mechanically moving the anvilin a spiral path to unthread the threaded portion from the formed nut,and thereafter ejecting said nut therefrom. 3. The method of forming athreaded nut which includes the novel step of subjecting a hollowmetallic blank to pressures between a coining die and the threadedportion of a central mandrel, said pressures being sufiicient to causeit ,to flow and conform to the contour of the coining die and threadedportion, thereafter mechanicallj revolving said mandrel in a descendingpath to unscrew the threaded portion from the nut, and thereafterejecting the nut from said coining die. I

- LEONARD A. YOUNG.

